The cam is a very critical part of an engines valvetrain. The cam is what lifts the valves into the combustion chamber allowing air to enter the cylinder. Cam profile selection is very critical on how an engine will run, and how log the cam will live. The cam along with the cylinder heads control how much air can enter the engine. The more air in the engine, the more power that can be made (within reason). This does not mean the most aggressive cam is the best one for you. You can get away with a fairly agressive cam on a carbureted vehicle. Be careful on a fuel injected engine as too much overlap will drop vacuum and will not allow the fuel injection to work correctly.
The Pontiac Fiero has some very interesting qualities, good and bad. It was built by GM in 1984 through 1988. The Pontiac Fiero was going to be a true GM sports car. It was a mid engine car as most exotic sports cars are. This means that the engine sits behind the driver. Having the engine behind the driver has many advantages in a sports car. This is why they are often used today in many kit car conversions. First the front to rear weight is usually close to 50/50 which would be a perfect balance.
Alternative fuels are continuously being looked at. Propane or LPG cars are already currently being used on buses and taxi cabs. Alcohol or ethanol can be produced from corn or other carbon based by products. Methanol is being replaced by ethanol in racing. Although it is a cleaner fuel the cost is generally higher and can be corrosive. It is already being mixed with gas in some places but only at a 10 percent mixture. MTBE is a manmade molecular chain gasoline, but has no real environmental advantage other than possibly elongating how long our oil supply lasts. The most exciting fuel is hydrogen. It can burn and only release water as a by product. The problem comes with the storage of the hydrogen. In order to have enough volume of hydrogen gas it has to be highly compressed. This is a little difficult as conventional compressors are not suited to this task. Most compressors only compress to 3000 psi, whereas 10,000 psi would be great for hydrogen storage. All cars could be converted to run with hydrogen.